The prior art is already aware of the concern and problem for handling and conveying sheets which come from a printing press, and these sheets are commonly folded and are colated and stitched or stapled and then trimmed and stacked. The industry is concerned about being able to move the sheets at a high speed which is sufficient to keep up with the speed of the printing press and to yet handle the sheets carefully and accurately so that they are properly aligned and can form a neat final product of a book or magazine or the like. Thus, sheets are commonly positioned in the so-called saddle position along a raceway on which the sheets are draped in an inverted V-position with the fold line at the top edge of the sheets. A chain system is commonly employed for pushing the folded sheets along the raceway and the sheets are stitched at the folded edge and they are then formed into stacks.
The present invention provides apparatus for conveying the folded sheets along the raceway and toward the trimmer or the like while moving the sheets at one continuous, and even constant velocity. Accordingly, a high-speed movement is achieved, and the sheets are accurately and neatly handled without damage or misalignment between the stitching process and the trimming process.
In accomplishing the aforementioned, apparatus is provided for receiving the sheets from the raceway and to lift the sheets into an elevating type of conveyor which lays the sheets flat on their sides and then moves the sheets into positions for stacking or the like. In accomplishing this objective, clamp pads are employed for straddling the folded sheets and pressing them together while lifting them from the transition of the raceway to the vertical elevating conveyor mentioned, and to do so without upsetting the relationship between the folded sheets and to do so at the high speed in continuous velocity mentioned.
A further object and accomplishment of this invention is to provided apparatus for the conveyance of folded sheets and to pass them through a caliper section of apparatus where the size of the sheets can be determined and to then continuously pass the sheets in a stream to where any sheets which have been detected to be a non-standard size are diverted from the stream and placed into a reject location. The reject sheets can then be reclaimed and placed back into the apparatus for proper sizing and colating and final movement to the final formation of the book or magazine.
The present invention also provides a method for conveying folded sheets of paper through a caliper section, a stitcher, and to a trimmer, all at one continuous, and even constant, velocity. A high velocity is achieved, and the sheets are handled without damage or misalignment.
Also, the method sorts out sheets which are not of a standard size, and those sheets are diverted from the path of the standard size sheets. This is accomplished while the sheets are continuously moving, and the method and apparatus therefore keep up with the high speed production of the printing press and the folder.